When the director walked the red carpet last week at the Gotham Independent Film Awards in support of his film "A Dangerous Method," he stopped to speak again with MTV News' Josh Horowitz, revealing which scenes in particular were the most challenging for Pattinson.

"Probably the last couple of days was where there was just a long, long, maybe 15-minute scene with Paul Giamatti, just the two of them in a couple of rooms," Cronenberg said. In "Cosmopolis," Pattinson plays Eric Packer, a young millionaire who just wants to get his hair cut. Things go awry when his limo gets stuck in traffic and a stalker, played by Giamatti, causes even more trouble.

Cronenberg said that one of the biggest testaments to Pattinson's skill as an actor was the effect he had on his Academy Award-nominated co-star. "They were both brilliant, and Paul was really impressed," he said. "If Paul's impressed, he's a good judge of other actors, and he said so publicly."

The director is simultaneously promoting "A Dangerous Method" and putting the finishing touches on "Cosmopolis." Cronenberg said that juggling both has never been an issue: "I've edited 'Cosmopolis,' and I'm about to go to Paris next week to do the sound mix of it, but I can switch over. It's like having two kids. When one kid comes through the door, you're there for that kid."